Necropsy On Dead Minke Whale That Washed Up On Nantucket Indicates Blunt Force Trauma

The dead minke whale that washed up on Nantucket's south shore in April appears to have suffered from blunt force trauma, according to the results of a necropsy performed by the Nantucket Marine Mammal Alliance and the New England Aquarium.

It is unclear, however, what the source of that trauma was, and the authors of the necropsy - or animal autopsy - stated it could be the result of several different scenarios from a vessel strike, to a conflict with aggressive whales, or a disease that led to self-trauma from floundering in the surf.

The 24-foot minke whale was discovered on April 25, 2024, near Madequecham Beach. It was removed from the beach and the necropsy was performed a day later by the Marine Mammal Alliance Nantucket (MMAN) team under the direction of MMAN team veterinarian Dr. Stephen St. Pierre and Dr. Charles Innis of New England Aquarium.

"The final diagnosis was suspected blunt force trauma as the cause of death," according to the report by MMAN. "This conclusion was based on the amount of hemorrhage and edema in the blubber and connective tissues of the caudodorsal lumbar, shoulder and ventral cervical regions apparently acquired prior to death. This could be vessel strike, or conflict with aggressive whales. The overwhelming cause of death of whales on the East Coast is vessel strikes and entanglements. Minke whales are also known to succumb to infectious disease, which could lead to self-trauma from floundering in the surf prior to death. Internal organs were too far deteriorated to determine any additional pathology. Autolysis happens very quickly."

Since 2017, NOAA Fisheries has been investigating an unusual mortality event (UME) for large whales in the North Atlantic. The minke whale UME began in January 2017. While Minke whales in the United States are not endangered or threatened, all marine mammals (including the minke whale) are protected under the Marine Mammal Protection Act.